$ { \left[\begin{array}{rr}{0} & {-1} \\ {2} & {1}\end{array}\right]+\left[\begin{array}{rr}{-2} & {3} \\ {1} & {-2}\end{array}\right] = {?} } $
To find the sum of two matrices, add the corresponding items between each matrix. ${\left[\begin{array}{rr}{0}+{-2} & {-1}+{3} \\ {2}+{1} & {1}+{-2}\end{array}\right]}$ Now, simplify: ${\left[\begin{array}{rr}{-2} & {2} \\ {3} & {-1}\end{array}\right]}$